Re: [PATCH v2] x86, mm: set NX across entire PMD at boot
From: Thomas Gleixner
Date: Sun Nov 16 2014 - 13:52:21 EST
On Fri, 14 Nov 2014, Yinghai Lu wrote:
> On Fri, Nov 14, 2014 at 6:46 PM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
> > On Fri, Nov 14, 2014 at 6:29 PM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote:
> >> should use attached one instead.
> >> 1. should use _brk_end instead of &end, as we only use partial of
> >> brk.
> >> 2. [_brk_end, pm_end) page range is already converted. aka
> >> is not wasted.
> > Are you sure? For me, _brk_end isn't far enough:
> > [ 1.475572] all_end: 0xffffffff82df5000
> > [ 1.476736] _brk_end: 0xffffffff82dd6000
> Yes. _brk_end should be small then &_end.
Wrong. _brk_end can move up to _end, i.e. to __brk_limit.
But it's safe to use _brk_end when mark_rodata_ro() is called because
extend_brk() is gone already at that point.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/